What is the most efficient way to migrate an SQL Server Express database from one server to another? I have several databases that need to be moved, and I want to do as little work as possible and avoid breaking anything.
Backup and restore.
You backup your database some location and you then restore from that location but you target a new database on your target server (overwrite any changes).
It's fast and straight forward. You can however, not use this to move databases cross different versions of SQL Server (it should be fine to use this to migrate from express to standard but the other way around might be problematic as the standard edition isn't subject to the same limitations as the express edition).